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O(nlogn) Algorithm - Find three evenly spaced ones within binary string
....3^n-1 not containing 1 in their ternary expansion) - its density is n^(log_3 2) (circa 0.631). So any checking if the set isn't too large, and then checking all pairs is not enough to get O(n log n). You have to investigate the sequence smarter. A better lower bound is quoted here - it's n1-c/(log(...
Extracting numbers from vectors of strings
...meric(gsub("([0-9]+).*$", "\\1", years))
or
# pattern is to just remove _years_old
as.numeric(gsub(" years old", "", years))
or
# split by space, get the element in first index
as.numeric(sapply(strsplit(years, " "), "[[", 1))
...
find() with nil when there are no records
...
Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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How does having a dynamic variable affect performance?
...Generator();
if (!method.IsStatic)
{
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Unbox_Any, method.DeclaringType);
}
var parameters = method.GetParameters();
for (int i = 0; i < parameters.Length; i++)
{
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCo...
Installing multiple instances of the same windows service on a server
So we've produced a windows service to feed data to our client application and everything is going great. The client has come up with a fun configuration request that requires two instances of this service running on the same server and configured to point at separate databases.
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How to include another XHTML in XHTML using JSF 2.0 Facelets?
...real world examples of advanced Facelets templating, check the src/main/webapp folder of Java EE Kickoff App source code and OmniFaces showcase site source code.
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Catch multiple exceptions at once?
...program flow, it just handles certain exceptions then lets the rest of the application deal with any other exception types.
– lkg
Jun 14 '11 at 19:13
30
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DateTime.ToString() format that can be used in a filename or extension?
...our file name.
Here i have provided example
string fileName = "fileName_" + DateTime.Now.ToString("MM-dd-yyyy_hh-mm-ss-tt") + ".pdf";
OR
If you don't prefer to use symbols you can try this also.,
string fileName = "fileName_" + DateTime.Now.ToString("MMddyyyyhhmmsstt") + ".pdf";
Hope this ...
How to hide close button in WPF window?
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Actually, this approach hides all three buttons (Min, Max and Close). Is it possible to just hide the Close button?
– newman
May 14 '13 at 14:58
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How do I generate random numbers in Dart?
...0.9 ... the result would be for example -0.32
– just_a_dude
Nov 7 '13 at 13:59
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